The six-episode show investigates the horrors of Dr. Christopher Duntsch, who botched back surgeries from his base at Dallas Medical Center and Baylor Plano.

The first episode tells the story of Shirley Mock of Garland. Duntsch operated on her spine when she was 71 in 2012, and he soon after convinced her that she needed an immediate emergency surgery at “South Hampton hospital.” Duntsch told Mock and her husband that it had the “most modern equipment.”

They arrived for the surgery, and “it looked like the place should’ve been condemned 20 years sooner,” Brandon Mock says.

The second surgery took six hours, and Duntsch butchered Shirley Mock’s spinal column, mangling nerves and leaving behind bone fragments and screws punched into flesh. She woke up in such pain that she thought she was dying, and no medication could help.